The use of sheet pile systems for retaining walls is know in the art. Examples of such systems include U.S. Pat. No. 6,135,675 to Moreau, U.S. Pat. No. 5,145,287 to Hooper et al., and U.S. Pat. No. 4,690,588 to Berger. Wood, steel, aluminum, and vinyl have traditionally been used to construct retaining walls. Each of these materials, however, has certain limitations. For example, wood is subject to rotting and insect infestation, and thus, has a relatively short life span as compared to the other materials. Steel is subject to corrosion, and because of its weight, requires additional equipment and manpower to install, thus increasing its overall cost. Aluminum, although lighter than steel and easier to install, is also subject to corrosion in certain applications. Vinyl, although lightweight and resistant to corrosion, lacks the strength of the other materials, and thus, is usually required to be used in conjunction with one or more of the other materials.
Composite components have been introduced to replace wood, steel, aluminum, and vinyl sheet pile components. Composite materials may be manufactured using a pultrusion process. In one type of pultrusion process, glass fibers are pulled through a resin bath where the glass fibers become saturated with a liquid thermosetting resin. Next, the coated fibers are formed to the proper shape using a forming guide or die. Finally, the reinforced material may be drawn through a heated curing die. Composite sheet pile components are stronger, easier to install, and longer lasting than their wood, steel, aluminum, and vinyl counterparts.
In a typical sheet pile retaining wall installation, pilings are driven into the ground using a vibratory hammer, vibratory plate compactor, jackhammer with a sheet shoe, or a drop impact hammer, among others. One or more pilings may be driven into the ground at the same time. Adjacent pilings may be interconnected to form a continuous wall. For example, a piling may have a “male” connector on one end and a “female” connector on the other end. The male connector of a first piling is mated with the female connector of a second piling, and the male connector of the second piling is mated with the female connector of a third piling, and so on, to form the retaining wall. One or more rows of horizontal supports, known as wales or walers, may be placed across the front or back face of the wall to lend additional support. Also, a cap and cap channel may be placed on the top of the wall.
The cap with a cap channel and wales may be connected to a tieback system, which secures the retaining wall. A tieback system normally includes a series of anchor members (or deadmans) and tieback rods. In a seawall application, for example, the tieback system has an anchor located on the land side of the seawall. One end of a tieback rod is attached to the anchor. The other end of the tieback rod passes through the pilings and is secured with a fastener on the sea side of the seawall. In most seawall applications, the tieback rod also passes through the cap and cap channel or wale. Thus, the cap, cap channel, and wale aid in distributing the retaining force exerted by the tieback system over the face of the seawall.
Prior art retaining wall typically use metallic (for example, galvanized, stainless steel, and resin treated steel, etc.) tieback rods. The metallic tieback rods are treated to resist corrosion, however, the metallic tieback rods inevitably corrode over time. The corrosion of the metallic tieback rod may also adversely affect the anchors and retaining wall to which the tieback rod is attached.
Thus, there is the need for a composite tieback rod that better resists the effects of corrosion, that will not adversely affect the anchors and retaining wall to which it is attached, and may be used in a tieback system having composite components.
Furthermore, prior art retaining walls typically use wooden wales. In addition to rotting and insect infestation mentioned above, the use of wooden wales present other problems. For example, the tieback rod and its fastener may protrude from the wale. The exposed end may damage anything coming into contact with the wale. For example, boats pulling up next to a seawall may be scratched, gouged, or even punctured by the tieback rod end protruding from the wale. To overcome this problem, countersink holes may be drilled into the wooden wale such that the tieback rod end and the fastener do not protrude past the face of the wale. However, drilling countersink holes increases the labor necessary to install the wale.
Thus, there is a need for a composite wale that resists rotting, insect infestation, and corrosion (among others), and that is formed with a recess that prevents a tieback rod end and its fastener from protruding beyond the face of the wale. Furthermore, a need exits for a retaining wall system that includes sufficient structural capabilities, which resists rotting, insect infestation, corrosion, and other detrimental effects, and which is lightweight and easy to install.